AnyRail
AnyRail software is usable for all scales of railroads including G. It comes with a number of predefined libraries that contain template track pieces that match various manufacturer products for maximum accuracy. G Scale manufacturers include Aristo-Craft, Bachmann, LGB, Peco Code 200, and Piko G. They offer free upgrades, email support, online manuals and a trial version (see Resources).
Rail Modeller
Rail Modeller software is specifically designed for Mac systems and will help you plan a model railroad in any scale. It features a 3-D mode which allows you to see how the track plan will look vertically as well as horizontally. It also offers the ability to design slot car layouts. The program is built for Mac OS 10.4, but compatible versions are available for older operating systems. Email support and a community forum is available for users as well (see Resources).
RR Track
RR Track is a program designed for Windows and will operate with any version of Windows from Windows 95 through Windows 7. It is a gauge specific scale modeling program, but it offers both standard G scale and G narrow gauge. G gauge bundles can be ordered directly from the website and all programs are sent by mail on CD-ROM. They also offer libraries of G scale accessories and downloads of G scale layout examples that have been completed (see Resources).
Cadrail
As the name suggests, Cadrail is a 3-D cad software that allows for layout simulations and multiple angles, object editors and design managers. Very precise and modifiable accessory, engine and rolling stock drawings are included. LBG is the only installed G library but the software allows for users to add new product lines (see Resources).
3rdPlanIt
3rdPlanIt is the latest version of El Dorado's rail planning software. Rather than rely on specific libraries, the program uses a standardized library that can be rescaled up or down. Users can change angles and roll and tilt to see the proposed layout from various points of view. It will also allow for 1:1 cross section printing for use as you build. 3rd PlanIt requires a software download, but will send a back up CD and printed manual for an additional fee (see Resources).